Hi tnt -- I wouldn't let your state of residence hinder you from applying. UNE accepts approx 70% of all applicants from Maine, but only about 30 people apply from the state each year. My point is that there is a lot of space in the class for non-residents. As far as your gpa/MCAT -- UNE looks more deeply into your application, such as extracurrics, volunteer work, interest in osteopathy. Definitely stress your interest in osteopathy in your person statement.
About answering the question of why you want to go to UNE -- look into the school itself and answer this question. Check out their web page. I had the chance to speak with current students, residents and graduates of UNE and I heard a great deal of positive feedback on the school. The campus is in a beautiful location. Plus, they were ranked by US News & World report in the tip 30 of all schools for rural medicine and family medicine if that means anything. There were many reasons why I chose UNE, so just do some investigating and find out for yourself why it would be a good match for you. If you have anymore questions about the school, I'd be glad to try and answer them. Best of luck!